Apple does not enforce unique naming for app schemes. If you use the same scheme as another app, iOS has no way of knowing which App to launch. In practice, this is a major source of confusion and bug reports. You’re much better off picking a unique URL scheme.

movies:// == badmyawesomemovieapp:// == good

Taking it Further

The true power of URL schemes is in the ability to perform specific actions as your app opens.